PowerWorld Simulator Quick Start Guide 2001 South First Street Champaign, Illinois 61820 +1 (217) 384.6330 support@powerworld.com http://www.powerworld.com
Purpose This quick start guide is intended to provide a brief explanation of the essentials to analyzing power systems with PowerWorld Simulator It is not comprehensive Greater detail is available in our full length training, on line or in person Other quick start guides discuss specific advanced features of Simulator For more details, visit http://www.powerworld.com/training/online training 2
Outline Opening a power flow case (raw, epc, pwb) Solving a case Browsing power system elements with the Model Explorer One line diagrams Limit Monitoring Settings 3
Opening an Existing Power Flow Case PowerWorld Simulator can open files in the following text based formats: Siemens PTI PSS/E *.raw file extension Common with FERC 715 filings and ISO cases GE PSLF *.epc file extension Common in the North American WECC Other specific formats for real time EMS models Simulator also has a proprietary binary format with *.pwb extension 4
Example Click the File Menu in the upper left Choose Open Case From the drop down box in the lower right, choose PTI Raw Data (.raw) Open the sample case Midwest.raw (available from the PowerWorld training website), or open any case that you need to analyze 5
Solving the Case For the data in a power flow case to be considered valid, a set of non linear equations must be solved First, open the Message Log from the Tools ribbon tab (Tools Log) 6
Next, choose Single Solution Full Newton, also on the Tools ribbon tab A series of nested loops should solve and a successful solution should be reported in the Message Log If the solution is successful, proceed to slide 15 Solving the Case 7
What if the Case Does not Solve? The case may not solve if: It was not solved by the entity that created the file It was solved, but with different controller settings than the Simulator defaults There are certain kinds of data errors If the case fails to solve, you will see a message in the log and a pop up window 8
Try to Solve with Controllers Disabled Unless the case was not solved by the entity that created the file, this will normally work Choose Tools Restore State before failed solution attempt Open Tools Simulator Options Check boxes Disable Automatic Generation Control (AGC) Disable Switched Shunt (SS) Control Disable LTC Transformer Control Disable Phase Shifter Control Click OK, then solve the case (Single Solution Full Newton) 9
Now Restore the Voltage Controllers Turn on the Switched Shunt Controllers First (uncheck the box in Tools Simulator Options ) Solve Power Flow (Single Solution Full Newton) Then turn on the LTCs Solve Power Flow Then turn on the Phase Shifters Solve Power Flow If the power flow fails to solve at any of these stages, it is likely that the controller option was not applied in the original solution Restore the system state, uncheck the last option, and re solve You may still try enabling the other controllers 10
Automatic Generation Control (AGC) Before you try to enable the AGC, ensure that the case was truly solved with AGC control The best way to check: Open Model Explorer (Case Information Model Explorer ) Open the folder Aggregations, then choose Areas Look at the ACE MW column If values are very large, then the case was probably not solved with AGC 11
Automatic Generation Control (AGC) If the ACE values are small, you can probably enable the AGC and solve the case Otherwise, you can either leave the AGC disabled, or enable it and adjust the area interchange 12
Area Unspecified MW Interchange Each Area can have an export specified which does not have a receiving end specified The Area display in the Model Explorer includes a column Unspec. MW Inter., usually on the far right These unspecified values should sum to zero. If they do not sum to zero, you have an export to nowhere When this occurs, the Area with the slack bus will be turned off AGC and all unspecified interchange will be sent to the island slack bus 13
What if Interchanges Don t Look Right or ACE Values are Large? In the Model Explorer, Open the folder Aggregations, then choose MW Transactions On the Case Info Toolbar, choose Records, Clear Transactions and auto insert tie line transactions Now try to re enable AGC and re solve the case 14
Examining the Data in the Case There are 3 primary ways to interact with the power flow case Model Explorer: spreadsheet like tabular displays Bus view one line diagrams (automatically generated) Other one line diagrams (user generated) We will next examine the use of the Model Explorer 15
Model Explorer Choose the Case Information ribbon tab, then Model Explorer 16
Explore Pane Fields Pane Object Types with no data grayed out Model Explorer Recent Tabs Toolbar Note: The options available on the Case Information right click local menu are also available on the Case Information Toolbar directly above the display 17
Model Explorer The left side initially contains the Explore pane Spreadsheet like case information displays are organized in folders that can be expanded or collapsed Click on an item with a grid symbol to open the corresponding case information display 18
Model Explorer Once opened, a case information display is contained within its own tab To close a case information display, click its X 19
Toolbar and Local Menu Many functions in Case Information Displays can be accessed by: Case Information Toolbar Local Menu (right click) Mouse over the buttons on the toolbar for a description of their function 20
Columns and Appearance All displays have a set of default fields These can be modified from the Fields pane, or with the Display/Column options on the toolbar or local (right click) menu 21
Display/Column Options Column Options Gray text means the field is already shown Colored Dots represent the field type Hints automatically appear giving a description of the field Fields organized by folder 22
Display/Column Options Column Options Choose fields from the Available Fields list. Then left click and drag into the Show these fields in this order list Use a wildcard find for a particular field Fields grayed out if already in display Number of frozen columns Also can click the Add or Remove Buttons to modify the fields shown Click Move Up and Move Down to change the order of the columns Change attributes of the display columns. Also, use toolbar buttons 23
Display/Column Options Display Options Will disable the area/zone filtering for a single case info display. Also available via a toolbar button Define a custom filter Also available via a toolbar button Change custom fonts and row heights Auto resize all column widths. Also available via a toolbar button Reset all values to default 24
Simple Sorting To sort a column, left click on the column heading. Click again to sort in the opposite direction SHIFT + Left Click will sort by Absolute Value Sorted Descending by Gen MW Note: Arrow showing sort direction Absolute Value Sort Click here to remove sorting 25
Color Conventions Font color denotes type of cell Black: read only Green: toggle between a set of allowable values (double click or click dropdown to change) Blue: user enterable Red: value at a limit Gray: disabled (mouse over for explanation) Purple: special or calculated 26
Area/Zone/Owner Filters Filtering can be applied to Areas, Zones, and Owners to simplify the Case Information Displays to show only parts of the system of interest Select Area/Zone Filters from the Case Information ribbon or the case information toolbar Example: set all areas to NO except a few of interest Click Set all No on Areas tab Toggle NO to YES in the Shown column by double clicking the cell. An element will appear in Case Information Displays if its Area, Zone, and Owner Shown fields are all set to YES 27
Bus View One Line Diagrams Another useful way to interface with a power system model Auto generates one line diagrams at each bus, one at a time, showing all devices connected to bus and all flows. Choose the Case Information ribbon tab, then Bus View 28
Bus View One Line Back and forward buttons Bus and Flow information Enter a name or number to go to a bus Click to find a bus Right click elements for information Left click circuit breaker to open/close Click links to jump to new bus 29
Bus View Oneline: Click Options > to reveal Number of Tiers specify 1 or 2 Show Hints As you move your cursor over an object it will show information Show Serial Buses Buses that are in series will be cascaded Show Equivalent Lines Change to hide/show equivalent lines Represent Multi Section Line Objects Show endpoints of MS Lines without intermediate buses Open Multiple Bus views Specify whether to create a new Bus View when a new one is requested. Choosing Prompt means you will be prompted each time Include Field Labels A description of what each field is will be shown. Change Bus Link Color The fill color of the bus links can be changed 30
One Line Diagrams Custom one line diagrams may also be created and edited by the user One line diagrams are well suited for widearea, regional, or local power system visualization One lines need only be created for the portion of the system of interest, but Simulator always models the ENTIRE system in calculations Simulator automatically links diagrams to the opened power system model 31
One Line Diagrams One lines may be geographic or schematic in nature For geographic diagrams, Simulator has built in borders for US states and counties, Canadian Provinces, and entire countries for the rest of the world For schematic diagrams, simply omit the borders and arrange system elements as desired 32
Creating a One Line Diagram Choose the File Menu, then New Oneline Simulator will automatically switch to Edit Mode if necessary and open a blank window to draw objects on the one line diagram 33
Insert Borders From the Draw Ribbon, choose Auto Insert Borders Select Region State or County for US Choose Map Projection (once set, do not change) Click OK to insert 34
Panning and Zooming Pan and Zoom to navigate around the one line diagram Panning Click and drag the one line background (not on any particular object) Use Arrow Keys (up, down, left, right) or Home, End, Page Up, Page Down to move more quickly Zooming Group of buttons on the Draw and Onelines Ribbons Zoom In with Ctrl Up Arrow key (or Ctrl Page Up to zoom more quickly) Zoom Out with Ctrl Down Arrow key (or Ctrl Page Down to zoom more quickly) 35
Use the Draw ribbon to add objects to the one line Drag and drop pallets are available for several object types Buses (common) Substations Areas Zones Choose Pale e for Buses Drag and drop buses from Palette onto the Diagram Object Palettes 36
Individual Insertion Objects may also be added to the diagram individually Objects are grouped by type, as in the Model Explorer For example, choose Network Bus, then click on the diagram where you would like to place the bus If necessary, change the bus number and other options, then click OK 37
Auto Insertion The layout of a one line diagram is generally determined by the location of buses, substations, areas, or zones Once these are in place, other objects that attached to them may be automatically placed 38
Arranging Objects on a Diagram You can generally relocate or reposition objects by clicking and dragging Certain object handles may be used for stretching, resizing, or rotating The Formatting group has options for changing the appearance of selected objects If you make a mistake, choose Undo Oneline Green Circle: Rotation Point Gray Square: For looks only Black Square: Resize Handle 39
Scaling Load It is often desirable to change the power system load from initial levels in the power flow case It is usually a good idea to begin with a case with load as close to the desired level as possible Small changes (about +/ 10% or less) can usually be performed without too much manipulation Larger changes often require adjustments, such as voltage controller settings, area transactions, generator unit commitment, and/or the use of the DC power flow. These topics are discussed in greater depth in our full training curricula. 40
Area AGC Settings Before scaling load, it may be desirable to change some default settings *.raw and *.epc files commonly use Area Slack control Area Slack means changes in area load are absorbed by generators at a single bus, the area slack bus This may be useful for holding constant the output of all other generators, but may not be realistic when making large changes to load Participation Factor control may be used to distribute the make up power requirement across the system 41
Participation Factor Control In the Model Explorer, open Aggrega ons Areas If desired, toggle the AGC Status field to Part. AGC Hint: click and drag from the lower left of a cell to fill other cells with the same value Areas that are initially Off AGC should normally remain Off AGC, as they often contain island slack buses or swing buses 42
Participation Factor Control To set generator participation factors, from the Tools Ribbon, choose Other Set Generator Part. Factors The default options are usually appropriate 43
Scaling Load Loads may be scaled individually from Model Explorer Network Loads usually edit the S MW and S Mvar columns Or in bulk from Scale Case on the Tools Ribbon 44
System Scaling Display Choose object to scale by Select specific objects to scale Enter either a scaling factor Or directly enter a new value Do Scaling scales the values, but leaves dialog open OK also scales the values, then closes the dialog 45
Scaling Example Scale by Area Choose one or more areas by toggling Scale? field to YES Specify new load with either Scaling multiplier, OR New MW value Click OK Re Solve the Power Flow (Single Solution Full Newton) NOTE: With Participation Factor AGC, it is usually not necessary to scale generation; this will occur on power flow solution. However, you may optionally scale generation on the System Scaling display 46
Scaling Notes With the AC power flow, several iterations of partial scaling followed by solving the power flow may be required to achieve a desired load With Participation Factor AGC, it is usually not necessary to scale generation; this will occur automatically with the power flow solution. You may optionally scale generation by Entering a Scale by factor or New Value for Generation, OR Check the box Scale Gen to Keep ACE Constant 47
Limit Monitoring Most power systems analysis tools make use of limits to define boundaries of safe, reliable operation Define settings for monitoring limits by selecting the Tools ribbon tab, then Limit Monitoring Settings. By default, ALL elements in the power system are monitored Use Limit Monitoring Settings to exclude power system elements that are of no interest for a particular study Different Line, Interface and Voltage limits can be assigned to each Limit Group, and each device within a Limit Group will adhere to its own Limit Group Settings 48
Limit Monitoring Monitoring may be done on buses (voltage), lines (MVA or Amps), transformers (MVA), interfaces (MW) An element is monitored only if ALL of the following conditions are met: Its Monitor field is set to YES Its assigned Limit Group is Enabled Its Area s Report Limits field is set to YES and its nominal kv is between its Area s Report Min kv and Report Max kv Its Zone s Report Limits field is set to YES and its nominal kv is between its Zone s Report Min kv and Report Max kv 49
Limit Monitoring: Key Components Area and Zone settings Monitored element types Limit Group settings Element s Monitor Field (YES/NO) Element s assigned Limit Group (all initially belong to Default ) 50
Limit Monitoring: Tabs Buses, Lines, Interfaces, and Nomograms show the individual elements of the power system important columns Monitor: specifies whether to monitor that specific element Limit Group: specifies the Limit Group that the element belongs to Area Reporting and Zone Reporting Specify which areas and zones to monitor Specify nominal kv range to monitor in each Modify/Create Limit Groups Specify limit levels and rating sets for lines, buses, and interfaces under normal and contingency conditions Most fields also present in the upper right corner of the dialog (Limit Group Values) 51
Limit Monitoring Example Use the B rating set for Lines & Transformers during Contingencies Ignore all radial lines and buses Report Limits only in a few areas, at 100 kv and above 52